Glossostigma cleistanthum — mud-mat
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Facts
Mud-mat is aptly named: it is a small, mat-forming plant of mudflats and lakeshores, with upright, opposite leaves the length of your thumb. It is native to Australia and New Zealand. The species has been introduced in New England recently, and also shows up in various sites in the mid-Atlantic states, where it is thought to have escaped from aquarium culture, and where it is likely dispersed by Canada geese and other waterfowl. Although it is not a nuisance plant in its native range, the state of Washington has actually declared it a quarantined weed, just in case.
Habitat
Fresh tidal marshes or flats, shores of rivers or lakes
New England distribution
Adapted from BONAP data
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
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enlargeCharacteristics
- Habitat
-
- aquatic
- wetlands
- New England state
-
- Connecticut
- Rhode Island
- Flower petal color
- white
- Leaf type
- the leaves are simple (lobed or unlobed but not separated into leaflets)
- Leaf arrangement
- opposite: there are two leaves per node along the stem
- Leaf blade edges
- the edge of the leaf blade is entire (has no teeth or lobes)
- Flower symmetry
- there is only one way to evenly divide the flower (the flower is bilaterally symmetrical)
- Number of sepals, petals or tepals
- there are five petals, sepals, or tepals in the flower
- Fusion of sepals and petals
- the petals or the sepals are fused into a cup or tube
- Stamen number
- 1 or 2
- Fruit length
- 1.4–1.8 mm
-
Clonal plantlets
- Bulbils
- the plant does not appear to have bulbils
- Bulblets replace flowers
- there are no bulblets where the flowers are located
-
Flowers
- Carpels fused
- the carpels are fused to one another
- Corolla morphology
- the flower has two prominent lips
- Corolla palate
- no
- Corona lobe length
- 0 mm
- Epicalyx
- the flower does not have an epicalyx
- Epicalyx number of parts
- 0
- Flower description
- the flower has a superior ovary, and lacks a hypanthium
- Flower petal color
- white
- Flower reproductive parts
- the flower has both pollen- and seed-producing parts
- Flower symmetry
- there is only one way to evenly divide the flower (the flower is bilaterally symmetrical)
- Flowers sunken into stem
- no
- Form of style
- NA
- Fusion of sepals and petals
- the petals or the sepals are fused into a cup or tube
- Horns in hoods (Asclepias)
- NA
- Hypanthium
- the flower does not have a hypanthium
- Inflorescence one-sided
- the flowers are arrayed in a spiral around the inflorescence axis or branches, or occur singly, or in several ranks
- Inner tepals (Rumex)
- NA
- Nectar spur
- the flower has no nectar spurs
- Number of pistils
- 1
- Number of sepals, petals or tepals
- there are five petals, sepals, or tepals in the flower
- Number of styles
- 1
- Ovary position
- the ovary is above the point of petal and/or sepal attachment
- Petal and sepal arrangement
- the flower includes two cycles of petal- or sepal-like structures
- Petal and sepal colors
- white
- Petal appearance
- the petals are thin and delicate, and pigmented (colored other than green or brown)
- Petal folds or pleats
- the petals of the flower do not have folds or plaits
- Petal hairs (Viola)
- NA
- Petal number
- 5
- Petal tips (Cuscuta)
- NA
- Scales inside corolla
- no
- Sepal and petal color
- the sepals are different from the petals
- Sepal appendages
- the sepals do not have appendages on them
- Sepal appendages (Oenothera)
- NA
- Sepal length
- 1.5–3 mm
- Sepal number
- 5
- Sepals fused only to sepals
- the sepals are fused to each other (not other flower parts), at least near their bases
- Stamen attachment
- the stamens are attached at or near the bases of the petals or tepals
- Stamen number
- 1 or 2
- Stamen position relative to petals
- NA
- Stigma position
- the stigmas are positioned at the tip of the style
- Style petal-like
- the styles are not petal-like
- Umbel flower reproductive parts
- NA
- Upper lip of bilabiate corolla
- the upper lip of the bilabiate corolla has two lobes
-
Fruits or seeds
- Achene relative orientation
- NA
- Achene shape
- NA
- Achene surface (Polygonum)
- NA
- Achene type
- NA
- Berry color
- NA
- Capsule color (Viola)
- NA
- Capsule splitting
- the capsule splits by two main valves, teeth or pores
- Fruit (pyxis) dehiscence
- NA
- Fruit features (Brassicaceae)
- NA
- Fruit length
- 1.4–1.8 mm
- Fruit locules
- two
- Fruit type (specific)
- the fruit is a capsule (splits along two or more seams, apical teeth or pores when dry, to release two or more seeds)
- Legumes (Fabaceae)
- NA
- Mericarp length
- 0 mm
- Mericarp segment shape (Desmodium)
- NA
- Other markings on berry
- NA
- Ovary stipe
- the ovary or fruit does not have a stipe
- Placenta arrangement
- the plant has axile placentation, in which the ovules are attached where the septa of a compound ovary are united, usually on the central axis, or to the septa themselves
- Rows of seeds in fruit (Brassicaceae)
- NA
- Schizocarpic fruit compression
- NA
- Schizocarpic fruit segments
- 0
- Septum in fruit (Brassicaceae)
- NA
- Wings on fruit
- the fruit does not have wings on it
- prickles on fruits
- the fruits do not have thorn-like defensive structures
-
Glands or sap
- Glands on leaf blade
- the leaf blades do not have glandular dots or scales
- Sap
- the sap is clear and watery
- Sap color
- the sap is clear
-
Growth form
- Growth form
- the plant is an herb (it has self-supporting stems)
- Lifespan
-
- the plant lives more than two years
- the plant lives only a single year or less
- Parasitism
- the plant is not parasitic
- Plant color
- the leaves or young stems of the plant are green
- Plants darken when dry
- no
- Spines on plant
- the plant has no spines
- Underground organs
- the plant has a rhizome (a horizontal underground stem with roots growing from it)
-
Leaves
- Bracteole number (Apiaceae)
- 0
- Bracts in plantain (Plantago)
- NA
- Final leaf segment length (compound lvs only)
- 0 mm
- Final leaf segment length to width ratio (compound lvs only)
- 0
- Final leaf segment width (compound lvs only)
- 0 mm
- Hairs on underside of leaf
- the underside of the leaf is not hairy, or it has very few hairs
- Hairs on upper side of leaf
- the upper side of the leaf is not hairy, or it has very few hairs
- Leaf arrangement
- opposite: there are two leaves per node along the stem
- Leaf blade base
- the leaf has no stalk
- Leaf blade base shape
- the base of the leaf blade is cuneate (wedge-shaped, tapers to the base with relatively straight, converging edges), or narrow
- Leaf blade edges
- the edge of the leaf blade is entire (has no teeth or lobes)
- Leaf blade length
- 4.5–57 mm
- Leaf blade shape
- the leaf blade is spatulate (spoon-shaped; narrow near the base, then suddenly widening to a rounded tip)
- Leaf blade surface colors
- the upper side of the leaf blade is relatively uniform in color
- Leaf blade width
- Up to 2 mm
- Leaf duration
- the leaves drop off in winter (or they whither but persist on the plant)
- Leaf form
- the leaves are green, with an expanded blade and a leaf-like texture
- Leaf spines
- there are no spines on the leaf edges
- Leaf stalk
- the leaves have no leaf stalks, but attach directly to the stem
- Leaf teeth and lobes
- the edge of the leaf blade is entire (has no teeth or lobes)
- Leaf type
- the leaves are simple (lobed or unlobed but not separated into leaflets)
- Leaflet number
- 0
- Leaves per node
- there are two leaves per node along the stem
- Pinnately compound leaf type
- NA
- Specific leaf type
- the leaves are simple (lobed or unlobed but not separated into leaflets)
- Stipels
- NA
- Stipule features
- NA
- Stipules
- there are no stipules on the plant
-
Place
- Habitat
-
- aquatic
- wetlands
- New England state
-
- Connecticut
- Rhode Island
- Specific habitat
-
- fresh tidal marshes or flats
- shores of rivers or lakes
-
Stem, shoot, branch
- Branched tendrils
- NA
- Hair between stem nodes
- the stem has no hairs between the nodes
- Hairs between stem nodes
- the stem has no hairs between the nodes
- Leaves on stem
- there is at least one full leaf above the base of the flowering stem
- Plant height
- Up to 5.7 cm
- Stem orientation
- the stems trail at the base, but may turn upwards at the tips
- Tendril origin
- NA
- Tendrils
- the plant does not have tendrils
Wetland status
Occurs only in wetlands. (Wetland indicator code: OBL)
In New England
Distribution
- Connecticut
- present
- Maine
- absent
- Massachusetts
- present
- New Hampshire
- absent
- Rhode Island
- present
- Vermont
- absent
Conservation status
None
From Flora Novae Angliae dichotomous key
1. Glossostigma cleistanthum W.R. Barker E
mud-mat. CT, RI. Shallow water or wet silt and mud of lakes and rivers, including fresh-tidal reaches. Originally thought to be Glossostigma diandrum (L.) Kunze, New England collections of this species have been confirmed as G. cleistanthum through molecular analysis. This species shows longer leaves than G. diandrum (mostly longer than 10 mm vs. mostly shorter than 8 mm). This new arrival to New England is easily confused with Limosella australis. However, it has a pair of leaves at each node and flowers with 2 stamens (vs. a cluster of leaves at each node and flowers with 4 stamens in L. australis).